title: Simultaneous determination of doxifluridine and 5-fluorouracil in monkey serum by high performance liquid chromatography with tandem mass spectrometry.
abstract: A reverse-phase high performance liquid chromatography method with electrospray ionization and detection by mass spectrometry is described for the simultaneous determination of doxifluridine and its active metabolite 5-fluorouracil in monkey serum. A liquid/liquid extraction with ethyl acetate (90%) and isopropyl alcohol (10%) was used to extract simultaneously doxifluridine and 5-FU which have considerable difference in the polarity. Optimum chromatographic separation was achieved on a Agilent Zorbax C(18) (100 mm x 2.1mm, 3.5 microm) column with a mobile phase of methanol-water (20:80, v/v). The flow rate was 0.2 mL/min with total cycle time of 5 min. The lower limit of quantification (LLOQ) was validated at 10.0 ng/mL of serum for both doxifluridine and 5-FU. Accuracy and precision of quality control (QC) samples for both compounds met FDA Guidance criteria of +/-15% with average QC accuracy of 95.5-105.0% and coefficients of variation of 1.1-9.5% in the 10-2000 ng/mL concentration range. This method demonstrated adequate sensitivity, specificity, accuracy, precision, stability to support the analysis of monkey serum samples.
authors.affiliation: Korea Institute of Toxicology, Daejeon 305-343, Republic of Korea.
authors.forename: Young-Ah
authors.initials: YA
authors.lastname: Woo
authors.forename: Ghee-Hwan
authors.initials: GH
authors.lastname: Kim
authors.forename: Eun Ju
authors.initials: EJ
authors.lastname: Jeong
authors.forename: Choong-Yong
authors.initials: CY
authors.lastname: Kim
mesh_terms: D000284:Administration, Oral; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000097:blood* / Q000493:pharmacokinetics; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004355:Drug Stability; D005467:Floxuridine / Q000097:blood* / Q000493:pharmacokinetics; D005472:Fluorouracil / Q000097:blood*; D016014:Linear Models; D008252:Macaca fascicularis; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000964:Antimetabolites, Antineoplastic; D005467:Floxuridine; D005472:Fluorouracil; C025034:doxifluridine